1. Field of the Invention
This invention relates to a floor panel.
More particularly, it relates to a floor panel which, at least at two opposite sides, comprises coupling parts, in the form of a male coupling part and a female coupling part, respectively, which allow that two of such floor panels can be connected to each other at said sides by providing one of these floor panels with the pertaining male part, by means of a downward movement, in the female part of the other floor panel, such that therein at least a locking in horizontal direction is obtained.
2. Related Art
Couplings, which allow coupling two floor panels with each other by providing one of these floor panels in the other by a downward movement, in practice are divided into two types, namely, a first type wherein the coupling parts provide exclusively for a horizontal locking without any locking in vertical direction, and a second type wherein both a horizontal and a vertical locking are provided.
The couplings of the first kind are also known as so-called “drop-in” systems. Floor panels equipped therewith at two opposite sides are known, amongst others, from CA 991.373 and JP 07-300979. As is evident from these patent documents, such “drop-in” systems often are applied at a first pair of opposite sides of the floor panels only, whereas then at the second pair of opposite sides coupling parts are applied which, in the coupled condition of two floor panels, provide for a vertical as well as a horizontal locking and which allow that two of such floor panels can be coupled to each other by means of a turning movement. Floor panels with such combination of coupling parts offer the advantage that they can easily be installed successively in rows, simply by coupling each new floor panel to be installed to the preceding row of floor panels by means of the turning movement and, when turning them downward, providing for that such floor panel simultaneously also engages in an already installed previous floor panel of the same row. Thus, the installation of such floor panel only requires a turning and putting down movement, which is a particularly user-friendly installation technique.
A disadvantage of floor panels with such coupling parts consists in that, due to the fact that there is no locking in vertical direction, height differences between the coupled floor panels may occur at the upper surface. For example, such floor panels in a first or last row of a floor covering can turn back upward if they are not held down by a skirting board or the like. Even when such floor panels are provided with a “drop-in” system at only one pair of sides, whereas at their other pair of sides, they are locked in horizontal as well as in vertical direction in respect to adjacent floor panels, height differences may occur between adjacent floor panels at the sides coupled by the “drop-in” system, amongst others, when two adjacent floor panels are stressed differently, or when one floor panel would warp and bend somewhat in respect to the other.
Couplings of the aforementioned second type, also called “push-lock” systems, try to remedy the aforementioned disadvantage by also providing a vertical locking. Such “push-lock” systems can be divided in two different categories, namely, one-piece embodiments and embodiments comprising a separate locking element, which is made as an insertion piece or forms part of such insertion piece, wherein this insertion piece may or may not be fixedly attached to the actual floor panel.
One-piece embodiments are known, amongst others, from the patent documents DE 29924454, DE 20008708, DE 20112474, DE 102004001363, DE 102004055951, EP 1.282.752 and EP 1.350.904. The known one-piece embodiments have the disadvantage that they work relatively unwieldy and that a well-working joining of two floor panels can not always be guaranteed.
Embodiments comprising a separate locking element, which assists in a vertical and possibly also horizontal locking between two coupled floor panels, are known, amongst others, from the patent documents DE 202007000310, DE 102004001363, DE 102005002297, EP 1.159.497, EP 1.415.056B1, EP 1.818.478, WO 2004/079130, WO 2005/054599, WO 2006/043893, WO 2006/104436, WO 2007/008139, WO 2007/079845, SE 515324 and DE 202008008597. Utilizing a separate locking element offers the advantage that the material thereof is independent from the actual floor panel and thus may be chosen optimally in function of the application thereof. In this manner, such insertion pieces, for example, may be realized of synthetic material or metal, which enables realizing strong, however, still easily movable locking portions, which can take up relatively large forces with a minimum contact surface.
From WO 2004/079130, embodiments of “push-lock” systems are known which comprise a separate locking element, which only assists in the horizontal locking between two coupled floor panels.